Simulation and experimentation on parameters influencing microwave-assisted extraction of bioactive compounds from Punica granatum waste and its preliminary analysis

Nowadays, the revalorization of high-value components of waste is the business goal for the development of food supplements in personalized nutrition, pharmaceuticals, and cosmetics. The objective of this study was to simulate and upgrade the extract quality of the medicinal plant Punica granatum L. peel powder by using microwave-assisted extraction (MAE). The central composite design was implemented for optimized parameters ethanol concentration of (50%), solvent: solid ratio (25:1 mL/g), extraction time (4 min), microwave power (450 W), on yield of 47.3%, total phenolic content of 432.05 mg GAE/g, DPPH reduction of 87.34%, was observed. The extract obtained after MAE of phenolic compounds contained 279.2 mg TAE/g DM of the highest total ellagitannin content and 25 mg QE/g DM of the flavonoid content of pomegranate peel powder. The structural characterization of bioactive compounds before and after MAE was performed using FTIR, SEM, and XRD. FT-IR technique was used to identify the functional groups in the pomegranate peel extract. The highest antioxidant active rich pomegranate peel extract proved that it can be utilized for the preparation of functional foods. This ‘green technology’ can be applied to various by-product processing and can be useful for upgrade studies for the value-addition of food products using an extraction approach. Practical applications: This study aims to establish a sustainable prototype for agro-industrial wastage management using an approach to process pomegranate peel that can deliver better economic and environmental outcomes. In this case, the application of the pomegranate peel extract is presented as an alternative to synthetic preservatives due to its highest antioxidant capacity. The advantage of the MAE procedure was the higher yield of up to 50% of extract per gram of peel powder. Our study demonstrates that statistically designed experiments allow for significant enhancement of the extraction process, which application could aid better use of natural resources and deliver more potent extracts than those obtained by currently recommended procedures.